Happy Holidays

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Happy holidays everyone! Today is December 25th, 2018, and we want to wish you all happy holidays, no matter what you celebrate. Be it the Winter Solstice, Christmas, Hannukah, Kwanzaa, Boxing Day, New Years Eve, Yule, Festivus for the rest of us, etc.! The Growers Network team has taken the day off, so look forward to more content soon!

Everything is fine with this picture.

So take the day or night off, sit back, and relax with your family! We’ll be back with more regularly-scheduled articles tomorrow!


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Surviving the Winter in a Greenhouse

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DryGair wants to talk about how greenhouse growers can keep their plants alive and healthy when the weather outside is frightful..

The DryGair Writing Team
Hadar Fuchs-Rubal | Nir Esquira | Rom Meir

The following is an article produced by a contributing author. Growers Network does not endorse nor evaluate the claims of our contributors, nor do they influence our editorial process. We thank our contributors for their time and effort so we can continue our exclusive Growers Spotlight service.


One of the greatest debates among cannabis cultivators is the question of indoor vs. outdoor growing. With the price of post-prohibition marijuana dropping steadily and the global energy market being as volatile as it is, it is the general consensus that greenhouse growing will inevitably become the most economically viable method to mass produce recreational bud

Growing in a greenhouse is great because it allows a grow to harness the natural energy of the sun. The sun’s light heats up the greenhouse, while providing full spectrum lighting, free of charge, all day long. But when winter rears its cold head, the tide shifts, and the concrete walls isolating a warehouse operation suddenly seem pretty warm and cozy.

We put together a few tips for surviving and thriving during the cold season, between see-through walls.


Heating is a Necessity


The most apparent problem during winter is the cold. While cannabis (especially Indica strains) can survive a bit of winter chill, it definitely doesn't thrive in such an environment. This makes heating a necessity. In order to be on the safe side, all heating equipment should be checked prior to the onset of cold conditions. During a harsh winter night, there is no place for down time. Greenhouse growers have already made the choice to aim for cost effectiveness, so in the spirit of efficiency, there are a few steps that can be taken to boost the effectiveness of heating:

  1. Before winter hits hard, do a complete greenhouse inspection and locate any points where air could leak out. These points are most likely to be found around vents, structural joints, doors, windows, and physical tears in the material. When these are all closed up, the hot air created inside can last much longer.
  2. When the space is insulated properly, additional layers of insulation can be added, such as specialized bubble wrap or other clear insulating materials to cover the greenhouse walls. Thermal screens can also be used to capture the heat during the night time. Simply let the sun do its thing during the day, and close the thermal screen when the sunlight dwindles. This traps the heat inside, giving a massive head start to nighttime heating.


Keep an Eye on Humidity


One of the perils of growing through the winter is that temperatures can drop suddenly, especially once the sun sets. This can trigger all sorts of problems with your humidity, because the plants in the greenhouse are constantly transpiring, releasing water into the air. When the temperature drops, the relative humidity spikes because the cold air cannot hold as much water. The real peril comes from the fact that, if not dealt with properly, the sudden drop in temperatures and consequent jump in humidity will cause water to condense within the greenhouse. Water droplets will appear nearly everywhere cold, making the entire operation incredibly susceptible to molds and fungi, such as Botrytis – bud rot.

Ventilating in order to reduce humidity, which is the traditional greenhouse method of eliminating humidity, is simply out of the question because of the heat loss it incurs, especially during the night. So the best option to deal with humidity is a dehumidifier.

An additional tip to assist both the dehumidification and heating efforts, is to have proper air circulation in the greenhouse, with the goal of keeping uniform conditions throughout the entire space. If climatic conditions fluctuate between different areas, you may see some plants thriving and others failing Furthermore, diseases such as bud rot only need to take root in one spot to infect the rest of the crops.

At DryGair, we designed our dehumidifiers to help circulate air, providing uniformity in addition to dehumidification, while removing over a gallon of water per kWh. Make sure to note the efficiency of your dehumidification choice (even if it’s not us!), and see what you can get the most value out of.


Supplementing Natural Light


Winter brings shorter days and longer nights with it, but this is not optimal for cannabis. Growers want to provide the optimal conditions for the plant's life stage, and winter’s short days just don’t cut it. Artificial lighting may be needed, and this need grows the further you are from the equator. Efficient lighting is important if want to optimize your electrical usage. Modern LED lights can save much as 40%, compared to CFL, and as much as a whopping 90% when compared to antiquated, incandescent bulbs.

Editor’s Note: HID bulbs can be used to generate heat in addition to their lighting output. HID fixtures also often take up less space in the greenhouse when compared to LEDs, which is important for maximum solar exposure. However, they also have higher electrical demands. There is significant debate in the cannabis community over lights, and we want to make sure to give everyone their credit. 🙂

One simple act to increase the amount of radiation absorbed from the sun is maintaining a clean and clear exterior. Replace old, hazy polyethylene sheets with new clear ones, and clean any snow, water or debris on the exterior of your greenhouse. These efforts can go a long way to increasing your plants' photosynthesis ability and reducing the need for artificial lighting.


Efficiency is the Key to Greenhouse Growing


Growing in a greenhouse requires paying a little extra attention so that even the small details are working for you. A little work goes a long way when it comes to optimizing crop growth in such an environment. But there's no need to worry -- a solid plan can carry you a long way.

We would like to take this opportunity to wish the Growers Network community happy holidays and a plentiful winter, from all of us here at DryGair.


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About the Authors

DryGair’s writers include a team of experienced engineers, agronomists, and economists. They specialize in climate control in closed growing facilities and practical solutions for effective climate management.


The Gift of Knowledge for Christmas

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We know that gift buying can be hard. That’s where Growers Network can help!


Good morning Growers Network readers! Some of you may have trouble buying gifts for your marijuana-enthusiast friends. Well I’m here to offer the gift the keeps on giving… knowledge!

Not from me though. To get that knowledge, you’re going to have to keep reading Growers Spotlight on the regular. I can’t very well package up my knowledge and deliver it to you in a singular book could I? Well, I probably could, but there’s people who would do it better than me anyway.

So, if you’re looking to get a gift for the enthusiast in your life, or you just want to find something to occupy your time and learn about Cannabis in the process, here are a few books I picked out, and why you might like them if you haven’t already read them:


1. The Cannabis Encyclopedia: The Definitive Guide to Cultivation & Consumption of Medical Marijuana

by Jorge Cervantes

This one’s a classic. Jorge Cervantes is a very well-known author and cultivator in the Cannabis industry, and he’s passed his knowledge on in a simple, easy-to-read book. The book has numerous pictures and illustrations to accompany his descriptions, and if you’re not convinced… just check out how positive the reviews are. The book is a smooth 596 pages, arranged in a pretty logical fashion.

So regardless of what level you’re at in cultivating Cannabis, the Cannabis Encyclopedia should be able to help you. You’ll sometimes hear it referred to as the Grower’s Bible, but that’s an older version of the book, or sometimes an entirely different book.

Side Note: Jorge Cervantes is actually a pseudonym. His real name is George Van Patten.


2. The Official High Times Cannabis Cookbook: More Than 50 Irresistible Recipes That Will Get You High

by High Times

We recently did an article on some Cannabis recipes for the holidays, but sometimes it just helps to have a cookbook handy with you in the kitchen. That’s where High Time’s cookbook can help you out. High Times magazine is well known for being one of the largest and oldest cannabis magazines in the industry, besides Sinsemilla Tips.

So why not present your friends or family with a cookbook they can confidently stroll into the kitchen with? And of course, don’t take our word for it. Check out the reviews.


3. Hydroponic Food Production: A Definitive Guidebook for the Advanced Home Gardener and the Commercial Hydroponic Grower, Seventh Edition

by Howard M. Resh

This one’s a little different from the other books we’ve already mentioned. This one is focused on general hydroponic agriculture -- a skill valuable not only in cannabis, but other commercial agriculture industries. If you, your friend, or your family member is looking to get a Controlled Environment Agriculture (CEA) degree, this book will be a must-read during their coursework.

The knowledge this book contains can be practically put on your resume. Many Cannabis grows are looking for growers that know more than just a random person on the street, and this book can help you there.

As always, we recommend you read the reviews.


4. Making Plant Medicine

by Richo Cech and Sena Cech

This book is not focused specifically on Cannabis, instead focusing on the creation of tinctures and herbal medicines. For anybody in your family who is interested in helping people as a caregiver or wants to get into making medicinal extracts, this book can help them.

Additionally, the book highlights important steps in the Cannabis curing process, such as drying and curing. These steps are critical to making the most potent medicine you can. The book also covers the processes in making salves and creams, teas and ingestibles, and other medicinal products. Make sure to read the reviews!


5. Weed the People: The Future of Legal Marijuana in America

by Bruce Barcott

This book focuses less on cultivation and medicine, and more on on the history and politics surrounding Cannabis. If you have a friend or family member who is big on political science, history, or just interested in the state of the world, this book may be the one for them.

If you want to know the history of Cannabis as it pertains to a modern environment, look no further. And of course, should you not want to take our word for it, check out the reviews!


If you or a loved one wants to learn more about the industry, it’s hard to go wrong with one of these books. That said, we’re always looking for more knowledge here at Growers Network. Is there a book we didn’t mention? Let us know in the survey below or on the forums!


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About the Author

Hunter Wilson is a community builder with Growers Network. He graduated from the University of Arizona in 2011 with a Masters in Teaching and in 2007 with a Bachelors in Biology.


How to Grow Cannabis 221 – Selecting Your Genetics

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Growers Network explains how you should choose the genetics you grow as a caregiver.


In our How-to-Grow Cannabis 100’s series, we discussed the differences between growing from seeds and growing from clones. We briefly touched upon a variety of advanced topics, but we didn’t get too much into the weeds (pun intended). Today we’re actually going to explore those weeds, and learn some more about how to pick what suits your needs.


Sativa? Indica? Hybrid?


If you’ve been around the Cannabis scene for any length of time, you’ve probably heard people talk about Sativas and Indicas. With a little bit of research, you may have even realized that people are talking about some of the proposed species (or subspecies) for the Cannabis genus.

But what does it actually mean to call a strain or cultivar a Sativa, Indica, or Hybrid?

In the simplest terms, referring to a Cannabis strain as a Sativa, Indica, or Hybrid refers to its dominant genetic heritage:

  1. Sativas are from wetter regions of the world, and exhibit longer branches, more spread-out leaves, and are associated with a “head” high. Many believe that sativa strains are associated with energy and euphoria.
  2. Indicas are from dryer regions of the world, and exhibit more “bushlike” behavior, with more tightly-spaced leaves and branches that help reduce water loss. Indicas are associated with a “body” high, and are considered responsible for feelings of sleepiness and relaxation.
  3. Hybrids, just as the name implies, are a hybrid of Sativas and Indicas. They exhibit characteristics of either grouping, and the same goes for their effects on the user.

However, be wary of overgeneralizations about how Cannabis strains make users feel. Many Cannabis users have reported Sativas having the purported effects of Indicas, and vice versa. Instead, as caregivers and cultivators, we should pay more attention to how our plants are growing, and what our patients want. The growth patterns of Sativas and Indicas matter to us as growers, but may be irrelevant to our patients and consumers.

When I’ve spoken with growers, they’ve generally told me the following as it pertains to growing Sativas and Indicas:

  1. Sativas tend to grow tall and lanky, making them more ideal for outdoor growing or growing in a large facility. They don’t require as much airflow, but require more space.
  2. Indicas tend to grow more bushy and thick, making them very useful for indoor and tent growing. Indicas require more maintenance to maintain airflow.
  3. Hybrids can display the properties of either group, so pick one that best suits your cultivation purposes.


To Autoflower or Not to Autoflower?


You may have noticed in the comparison chart I posted above, there was a tiny species/subspecies named C. ruderalis. This particular variant is a ruderal species/subspecies of Cannabis, found natively in Slavic countries. The reason this particular variant of Cannabis is important is because it features a trait that no other variant of Cannabis exhibits: The ability to autoflower.

Is this what you mean by autoflower? Image courtesy of Wikipedia.

See, most other varieties of Cannabis (Sativa, Indica, Hybrid) flower in response to photoperiod and scotoperiod. Autoflowering strains, on the other hand, flower after a certain amount of time has transpired. Autoflowering strains tend to be smaller (because they are generally hybrids with ruderalis), but require less input, making them convenient for those who prefer a more hands-off approach.

Editor’s Note: We should note that there is a stigma among professional growers against autoflowering strains, because you sacrifice an element of control due to their autoflowering nature. Additionally, autoflowering strains are crossed with the wild type of ruderalis that is divergent from the more cultivated Sativas and Indicas. One grower likened ruderalis to coyotes while Sativas/Indicas are domestic dogs. You may have a similar outcome, but one is domesticated, and the other is tamed.


Picking a Strain


“Now all of this info is great,” you might be thinking. “But how do I select the right strain?” Well, I hear your thoughts prospective grower, and I have the answer.

I can read minds. AHAHAHAA.

The answer is that you need to ask your patients what they want, and then do some research for what best matches what they’re asking for. Some patients may want a strain to help them sleep. Some patients may want a strain that helps with pain. Some may want a strain that calms them, or may want a strain that energizes them. Luckily, websites like Leafly can help you find strains that are supposed to have those effects.

The important thing as a caregiver is that you start with what your patients want. As we move into the more professional side of Cannabis, strain selection will focus almost entirely on your consumers’ desires.


So that’s it for selecting your genetics. Let us know what you think in the survey below or on the forum! In a future article, we’ll cover how to acquire the strains you like, how to maintain a stock of useful genetics, and how to breed your own genetics.


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About the Author

Hunter Wilson is a community builder with Growers Network. He graduated from the University of Arizona in 2011 with a Masters in Teaching and in 2007 with a Bachelors in Biology.


Five Holiday-Themed Cannabis Recipes

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Pass the cannabutter! In the spirit of the Winter Solstice, Growers Network publishes some recipes that are sure to spice up (or mellow out) the dinner table.


As much as cannabis users like to smoke a bowl, take a doobie, or vape away, sometimes we want something a little more… tasty. To that end, we’re discussing cannabis recipes that are themed for the holidays.


#1. Cannabutter (or Cannaoil)

Cannabutter (or Cannaoil) is the basis for a lot of other cannabis recipes, so we’ll start with it. It is possible to make cannabis-infused sugar as well (our Canna Cribs Episode on Phat Panda covers that), but it requires some extraction experience. Cannabutter, on the other hand, does not require too much technical expertise.

What you’ll need:

  1. 1 Cup of Water
  2. 1 Cup of Butter (or oil if you prefer)
  3. 1 Cup of Cannabis (Strain of your choice)

Step #1:

We’ll need to start by decarboxylating our cannabis. In Digamma’s Treatise on Decarboxylation, we learned that raw cannabis does not contain the active compounds we want, such as THC or CBD. Instead, raw cannabis tends to have the acid precursor forms of these chemicals, namely THCA or CBDA.

In order to decarboxylate our cannabis, we’ll need to give it some heat, but not enough to cause it to ignite, otherwise you’ll be hotboxing your oven. You’ll want to set your oven to about 250° Fahrenheit (120° C) and place your buds or ground cannabis onto a baking sheet with parchment paper for about 30 to 40 minutes. You can decarb at higher temperatures for faster, but you may end up with less even decarboxylation, reducing the potency of your cannabutter. Make sure to regularly shake and move your buds so that they heat evenly.

Step #2:

Once the buds have dried out and been heated, you’ll want to grind them up in a mortar and pestle, or a Magic Bullet. This will make it easy to put into the butter.

Step #3:

Melt the butter in a saucepan with the water. The water will help regulate temperature, we’ll get rid of it later. Don’t boil the water or butter -- let the water simmer gently. As the butter melts, pour in the ground cannabis and stir thoroughly. Let simmer gently for two to three hours, stirring occasionally. Do not let the butter burn or water boil -- try to keep the temperature between 160-200° Fahrenheit.

Step #4:

Once most of the water has evaporated from the mixture, you’ll want to pour the cannabutter over a cheesecloth (or similar filter) and into a container of your choice. Don’t pour it while hot! Let it cool a little bit before pouring, but not so much it resolidifies. The cheesecloth will help strain out the undesirable plant materials.

And there you go! Cannabutter, ready to serve or to be used in other recipes. Just make sure to keep this away from any kids!


#2. The Classic Brownie


This is where your cannabutter (or canna oil) can really come in handy. You don’t need to go to any fancy marijuana cooking website to make infused brownies now! Instead, you can substitute any butter, margarine, or oils in recipes with your cannabutter or cannaoil.

So next we’re going to take a classic brownie recipe and swap out the normal butter for cannabutter. For this recipe, you’ll need the following:

  1. ½ cup of cannabutter
  2. 1 cup white or brown sugar
  3. 2 eggs
  4. ⅓ cup cocoa powder
  5. ½ cup all-purpose flour
  6. ¼ teaspoon salt
  7. ¼ teaspoon baking powder

And for the frosting:

  1. 3 tablespoons of cannabutter
  2. 3 tablespoons of cocoa powder
  3. 1 tablespoon of honey
  4. 1 teaspoon of vanilla extract
  5. 1 cup of confectioner’s sugar

You can follow the instructions for the rest of the recipe here, or you can use your own brownie recipe.


#3. Cannabis Applesauce


Applesauce goes great with a lot of things and is great for people of all ages (Just don’t give this to kids. Cannabis applesauce is not for kids). It can go with breakfast, latkes, dinner, nearly everything. If your grandparents or parents like to medicate, this is a great option for them. The applesauce doesn’t require a whole lot of input, so you can generally do other things while you’re cooking it.

What you’ll need:

  1. 3 lbs. of apples of your choice -- can be sweet, tart, whatever you prefer.
  2. 4 tablespoons of cannabis-infused glycerine. The recipe to make cannabis-infused glycerine can be found here.
  3. Cinnamon (to whatever amount you prefer)
  4. A large saucepan

Step #1:

Core the apples and chop them into smaller bits. The smaller the bit, the faster it’ll cook. Put the pieces in a saucepan and move over medium heat until the apple pieces are soft (can take an hour or two). Stir regularly.

Step #2:

Once you see little pools of juice forming around the apple bits, add some cinnamon to the applesauce while maintaining heat. You can mash the apple bits to speed up the process.

Step #3:

Once the applesauce has reached a consistency you like, you can pour in the cannabis-infused glycerine and stir. Once it has been thoroughly mixed in, the applesauce is ready to eat. You can eat it hot, or cool it in the fridge -- whatever fits your fancy!


#4. Cranberry Walnut Salad


This one’s a classic for any gathering, so why not make it a family couch day?

Here’s what you’ll need for the salad:

  1. 4 cups baby spinach (or lettuce if you prefer, spinach is better)
  2. 2 fuji apples (thin-sliced)
  3. ⅓ cup feta cheese
  4. ⅓ cup craisins (cranberry raisins)
  5. ½ cup of walnut pieces

And here’s what you’ll need for the vinaigrette:

  1. ¼ cup of cannabis-infused oil
  2. ¼ apple cider vinegar
  3. ½ teaspoon dijon mustard
  4. 1 teaspoon brown sugar
  5. ¼ teaspoon garlic powder
  6. ¼ teaspoon oregano
  7. ¼ teaspoon basil
  8. ½ teaspoon salt
  9. ¼ teaspoon black ground pepper

Instructions are pretty simple. Stick all of the vinaigrette materials into a blender to make it smooth. Wash the baby spinach and slice the apples, then put them in a bowl together, throw in the feta, craisins, and walnut pieces, give it a mix, then drizzle the vinaigrette on top when ready to eat and give it a toss.


#5. Pot Corn


Movies are a family favorite, and popcorn mixes perfectly with movies! Obviously, if you have kids, you may want a separate bowl of popcorn for them, but for mom and dad (and grandma!), the special popcorn bowl will add a whole layer of fun.

You can make the popcorn in a popcorn maker and pour melted cannabutter over them, or you can cook the popcorn and cannabutter together in a skillet, whatever you choose to do. Top it off with a dash of salt to taste and voila! Perfect cannabuttered popcorn.


Well there you have it. Five great holiday and Christmas-themed cannabis foods! Do you have any family favorites? If so, let us know in the survey or comments!


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About the Author

Hunter Wilson is a community builder with Growers Network. He graduated from the University of Arizona in 2011 with a Masters in Teaching and in 2007 with a Bachelors in Biology.


Growers Network’s Pest Profile: Aphids #2

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In this series of articles, Growers Network talks about a few of the most common Cannabis pests you need to watch out for. Today’s topic: Aphids.


If any of you have spent any time in a garden, or even nature, you should be familiar with today’s pest: aphids. Aphids are found nearly everywhere there are plants on Earth, but tend to show up in regions that favor insect life (temperate to tropical). These little sap-suckers can make your life difficult, and can often be hard to get rid of.

So, without further ado, let’s explore the science of aphids.


Quick Look

  1. Common Name: Aphids, greenflies, blackflies, or plant lice
  2. Scientific Name: Aphids belong to the order Hemiptera, and are of the superfamily Aphidoidea
  3. Symptoms: Increase in disease incidence in plants, stunted growth, stunted or dying leaves and stems
  4. Timing: Any time


Aphids


Aphids are particularly annoying plant pests for several reasons:

  1. They like to hang out on the undersides of leaves and in shade, where they can be difficult to reach.
  2. Aphids drink the sugary-sap of most plants, often stunting or inhibiting growth of the plant. Sufficient numbers of them can kill plants entirely by drinking the sap dry.
  3. They often serve as carriers of plant diseases, and will transmit diseases to plants they insert their proboscis into.
  4. They can reproduce sexually or asexually -- a single female can theoretically infest an entire grow, and they can switch to sexual reproduction when stressed.
  5. Other insects like to feed off of the honeydew that some aphid species secrete. Ants in particular will “farm” aphids that produce honeydew, so if you have an aphid problem, you may soon have an ant problem to follow.
  6. Aphids can fly, and will be carried on the wind while they look for their ideal host plant.

An aphid giving birth while eating. The eating never stops.

As you can probably see, aphids are pretty bad for growing crops. Luckily, the vast majority of them are not microscopic and can be discovered with the naked eye before they become too big a problem.


Prevention


Prevention will largely depends on your growing facility. If you’re outdoors, you will need to consistently check your plants for any signs of an infestation. If you’re indoors or in a greenhouse, aphids should appear less frequently, but it’s still worthwhile to check regularly.

From there, there are a number of different approaches you can take to prevent aphids. Some methods may prove more useful than others:

  1. Natural predators such as ladybugs, mantids, assassin bugs, and nematodes can stop an aphid infestation before it really takes off. Some growers opt to regularly release these beneficials on or near their plants.
  2. Essential oil sprays will deter aphids, or can kill them. Soapy water sprays can also clog up aphid probosci, resulting in early deaths for the aphids.
  3. Plant companion plants that repel or attract aphids away from the cannabis. Some websites suggest marigolds and other flowering plants can attract aphids, while strong-smelling plants like onions or garlic can repel aphids.
  4. Indoor or greenhouse facilities that are designed with positive pressure will generally keep aphids out. The aphids will be unable to fly inside.


Treatment


Treatment of an infected grow will depend on the severity of the infestation and your grow. Hopefully you caught it early and can treat it relatively simply! Be sure to treat them as soon as you find them, or you may find yourself with an ant infestation or diseases spreading around your grow.

If Outdoors

  1. Strong blasts of water (IE from a hose) can knock aphids off of plants. However, this won’t kill the aphids.
  2. Beneficials such as ladybugs, assassin bugs, mantids, and nematodes can be released and will eat the aphids. These predators will generally stick around in the environment, although regular releases may help.
  3. Soapy water is known to clog up aphid probosci, killing them. If you find a group of them, get a spray bottle and mix 1 part dish soap with 10 parts water, and you have a pretty effective solution for removing aphids that is environmentally friendly.

An aphid’s worst nightmare.

If Indoors

  1. Most predatory beneficials should work indoors, including ladybugs, assassin bugs, mantids, and nematodes. However, release of these beneficials may need to be more frequent if they die out.
  2. Any insecticidal spray should kill aphids. Environmentally-friendly insecticides such as essential oils, neem oil, and more should work well.
  3. The soapy water trick, as mentioned above, should also work.


Conclusion

And there you have it. Aphids can be a real danger to any grow operation, but they’re probably one of the easier pests to treat for. Keep a vigilant eye and treat the problem before it becomes serious! And as always, stay tuned to Growers Network for more information about beneficials, diseases, and pests!


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About the Author

Hunter Wilson is a community builder with Growers Network. He graduated from the University of Arizona in 2011 with a Masters in Teaching and in 2007 with a Bachelors in Biology.


How to Grow Cannabis 214 – Strategies for Growing

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In today’s article, Growers Network wants to improve your growing techniques by taking some time to think about the… “art” or “philosophy” of growing.


I know what you’re thinking… “I’ve had enough with planning, let’s get to growing!”

Hold on there, bucko! Now that we’re at the caregiving level, we should start thinking about the future. When you’re growing for yourself, it’s not the end of the world if things don’t turn out quite as you expected. But now we need to learn from our mistakes, and start thinking about safer and better ways to produce our cannabis. So without further ado, let’s cover a few important points to up your game…


Grow Journals


You may read about experienced growers talking about taking notes or taking lots of data. What data are they talking about?

Well, they’re talking about having a journal where they record everything they did. Some of them have multiple journals lying about their grow, and some even make it part of of their standard operating procedures (SOPs). Some of them are very detailed, some are little more general. Here’s what you should know for creating your own grow journal:

  1. Have a central repository for information you record.
    1. This could be a physical journal or diary, this could be your phone or a computer, or it could even be an app like GrowDiaries.
  2. Record times and dates
    1. Turn on the lights at 6:00 AM? Make a note of it. In the second week of flowering? Make a note of it.
  3. Record amounts used
    1. Added 500 mg of nutrients to 2 L of water? Put it down, and date it.
  4. Record pests or problems that arise.
    1. Part of a grow journal is not just to learn what you do right, but what you do wrong. If something grows wrong, make a note. Then note how you fixed it (or didn’t).

Once you’ve repeated this process through several grow cycles, you’ll have a record of what has worked best for you, and what hasn’t, and you’ll be able to come up with a standard set of procedures for your grow.

And journaling doesn’t need to stop there. You can also record additional information such as biomass, dry weight, lab results, and more. This information may be useful in the future should you choose to use services that analyze your data, like Cannabis Big Data. Companies that analyze your data can help guide future practices as well.


Organics vs. Synthetics


This is a debate that has raged on throughout the entire agricultural industry, and not just in the cannabis industry. What are better methods for production? Organic, or synthetic?

Well you dear grower, are obviously unbiased and use the scientific method. Some of this stuff sounds good, some of it sounds kind of scary, but we should be equipped with the best knowledge available to make a decision.

First, we should make a few points:

  1. Organic, in this context, generally refers to the USDA’s (or other government agency’s) definition of organic farming practices. Organic methods favor sustainability and biological processes over non-biological and unsustainable practices, but not always.
  2. “Synthetic” is a broad term applied to a large number agrochemical companies and their products. It is generally used in a negative context in discussions, but not all synthetics are necessarily bad.
  3. The terms “organic” and “synthetic” can have very different meanings in other contexts. For example, in chemistry, organic simply means any molecule that contains carbon. Under that context, DDT is chemically organic, but not agriculturally organic.
  4. The terms “natural” and “unnatural” are basically meaningless in scientific and agricultural contexts. These terms are generally only used to make rhetorical points rather than provide practical advice.

For the purposes of our articles, we will try to focus on sustainable growing practices and stray away from particularly dangerous chemicals. However, don’t discount the utility and power of synthetics. Should a time arise when there are no good organic solutions, synthetics may be able to help. As a grower, you should be aware of all the tools available to you, and pick the best option based on what experience and research shows.


Pest Management


The last thing I want to bring up in this planning article is pest management. Whether you like it or not, pests are nearly everywhere. How you deal with them matters, and it may matter to your patients (or customers) too. As caregivers, we don’t want to just be reactive, we want to be proactive. If we are proactive, we can avoid a lot of problems before they become a headache. As the old adage goes, “a stitch in time saves nine.”

Let’s take a look at a specific example: Powdery mildew. Treatment after you’ve discovered powdery mildew is often very expensive and time consuming, and possibly dangerous should you decide to use fungicides. Prevention is significantly cheaper and less of a headache -- you have to control humidity in your grow.

Proactive pest management goes hand-in-hand with organic farming practices, particularly something referred to as IPM, or Integrated Pest Management. You can learn more about IPM here.


Conclusion


And that covers some of the “philosophy” of growing. As we advance in our growing skill and knowledge, we want to improve how we think about the act of growing. In psychology, this is called “metacognition,” and it’s a good idea to apply throughout your grow and your life. I hope you’ve learned something! Let us know in the survey or comments below.


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About the Author

Hunter Wilson is a community builder with Growers Network. He graduated from the University of Arizona in 2011 with a Masters in Teaching and in 2007 with a Bachelors in Biology.


5 Cannabis-Themed Holiday Gifts

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We thought we might take a deviation from our normally-scheduled publication and have a bit of fun for the season of festivities!


Most people have trouble finding the perfect gift for their relatives. After all, if your relative has money, they usually already have the things that they want. If your relatives don’t have money, it feels like a cop-out to give them money instead of a gift.

But you know what’s never a bad gift? Flowers.

So without further ado, let’s go over 5 Cannabis-themed holiday gifts, and see if we can’t find something that all of your relatives can enjoy!


#1. An Ounce


It’s hard to go wrong with a plain ol’ jar of good flower. After all, if you’re an adult in a recreational state, why not? You’ll get a few days worth of enjoyment out of an ounce of cannabis (or hours if you’re particularly enthusiastic). So why not drop by your nearest dispensary and pick something good up?


#2. A Vape and E-liquid


For the cannabis users in your life who prefer a more casual cannabis experience, vapes are a great choice. A good vape provides ease-of-use, discretion, and comfort that a joint, bong, or dab might not. Always read the reviews for the vapes you buy. Sometimes things that are expensive are worse!


#3. Cannabis Apparel


Now I know what you’re thinking, “People look silly when they wear weed apparel.” After all, I’m sure most of you have seen that guy at conventions who wears the giant marijuana costume.

But no, we’re talking something a little classier than that. Have you seen some of the cool stuff coming out of cannabis culture these days? There’s shirts celebrating THC, there’s UV-protective clothing, and there’s even cannabis-themed jewelry! If your relative really appreciates cannabis, they will appreciate classy apparel.


#4. A Stash


Not cutting it anymore.

Of course, if your relative has pets or kids, it’s important that they have a safe place to stash their goodies that won’t attract the youngins or furry friends. And that’s where an odor-resistant bag comes in handy. Check out some of this sweet luggage that can serve to hide odors and keep your flowers safe!


#5. A Yuletide “Tree”


This one may take a little bit more work, but in our “How to Grow” series, we’re explaining the steps on how to grow your own cannabis. Some plants can grow to be the size of small trees -- perfect for hanging some tinsel and decorations off of!

It’s festive, non-denominational, and while it may be flammable, at least you’ll have fun if it goes up!

So what do you think? Do you have your own ideas for cannabis-related gifts? Join the discussion on the forum now!


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About the Author

Hunter Wilson is a community builder with Growers Network. He graduated from the University of Arizona in 2011 with a Masters in Teaching and in 2007 with a Bachelors in Biology.


The Ultimate (Practical) Vapor Pressure Deficit Guide

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Peter Koverda of Pulse Labs takes us through a step-by-step process for calculating VPD, and gives us some general rules of thumb to follow.


Disclaimer

This article was originally published on Pulse Lab's blog. If you would like to read the original article, click here.


Editor’s Note: We’ve dedicated several articles to VPD before, but we felt this article stood out because it actually tells you how to calculate VPD and apply it practically to your grow. Please let us know your thoughts in the survey below. Additionally, Pulse Labs have made a custom calculator and chart available for you to download below, so keep an eye out for that!

Many growers will tell you that mastery of your grow comes from humidity control, and they’re not wrong. But humidity means so much more than a simple relative humidity measurement -- it means planning out precise humidities that ease stress on your plants at the right time, and stress your plants at the right time.

Unfortunately, relative humidity isn’t a good tool for planning. Relative humidity does not tell you how much water is actually in the air at any given moment, nor does it tell you where the dewpoint is or how much stress your plants are actually experiencing.

VPD helps you identify the correct range of temperature and humidity to aim for in your grow space and plan accordingly. With VPD you can achieve the best results while avoiding pest and environmental problems. You can achieve much tighter control over plant transpiration rates, stomata opening, CO2 uptake, nutrient uptake, and plant stress.

If you master VPD, you truly master your environment, and become better grower.

  1. What is VPD?
    1. Vapor Pressure, Temperature and Humidity
  2. How to Calculate VPD
    1. Air VPD
    2. Leaf VPD
    3. VPD Chart and VPD Calculator 📊
  3. Why is VPD Important?
  4. VPD and Indoor Growing
    1. VPD Changes With Temperature and Humidity
    2. VPD During Different Stages of Growth


What is VPD?


Vapor Pressure, Temperature, and Humidity

VPD stands for Vapor Pressure Deficit, but what does that actually mean?

Air is made up of many gases. Air is about 78% nitrogen, 21% oxygen, and 1% other gases. Water vapor, the gaseous form of water, is one of those other gases. The amount of water vapor in the air (expressed as pressure) is called “vapor pressure”.

Editor’s Note: Most atmospheric composition calculations don’t include water, due to significant variations in temperature between the layers of the atmosphere. On average, water vapor accounts for about 0.25% of the Earth’s atmospheric mass.

Air can only hold a certain amount of water vapor at a given temperature before it starts condensing back to liquid water (in forms such as dew or rain). The maximum amount of water vapor that air can hold at a certain temperature is called “saturation vapor pressure” or SVP.

As air gets hotter, the amount of water that the air can hold (its SVP) increases. As air cools down, the SVP decreases, meaning that the air can’t hold as much water vapor. This is why there is dew all over everything after a cool morning. The air gets too full of water, and the water condenses out. When water comes out of the air from reaching this maximum, it is called the dewpoint.

Similarly, the current actual amount of water vapor in the air is called the “actual vapor pressure” or AVP.

Some key points:

  1. AVP / SVP x 100 = RH%
    1. That’s right, RH is just the proportion of water the air is currently holding vs. its maximum capacity. That’s why it’s called “Relative” Humidity.
  2. The maximum the AVP can be is the current SVP.
    1. That means RH = 100%.
    2. Editor’s Note: If AVP reaches SVP, any additional moisture will precipitate out of the air.
  3. VPD = SVP – AVP
    1. VPD: How much more room there is in the air for more water vapor. It’s as simple as that. Now you get why it’s called the Vapor Pressure Deficit.


How Do You Calculate VPD?


To calculate Air VPD you just need two things: temperature and humidity. However, like any good calculation, there are a couple of steps.

How to calculate air VPD:

  1. Figure out the SVP
    1. SVP = 610.78 x e(T / (T +238.3) x 17.2694))
      1. e is a mathematical constant.
      2. T is in degrees Celsius
      3. The result, SVP, is measured in pascals (divide by 1000 to get kPa)
  2. Calculate the VPD
    1. SVP x (1 – RH/100) = VPD

However, since the inside of a plant is water, plants feel a different VPD than just the normal air VPD. If you want to figure out what’s going on with the plant, you need to consider the cooling effect of evaporating water as it exits the leaves’ stomata. To calculate this, you need to know the difference between the air temperature at canopy level, and the temperature of the leaves. An IR thermometer is particularly useful for this.

How to calculate leaf VPD:

  1. Figure out the air SVP (ASVP)
    1. Same formula as getting the SVP for air VPD
  2. Figure out the leaf SVP (LSVP)
    1. It is the same formula as ASVP, but you use the leaf temperature in your calculation (typically 1-3 °C or 2-5 °F cooler). This is where that IR thermometer comes in handy.
  3. Leaf VPD = LSVP – (ASVP x RH/100)

VPD Chart and VPD Calculator 📊

Below is a VPD chart in degrees Fahrenheit, for flower stage, with a 0° offset for leaf temperature.

If you want to get the chart maker to make your own custom chart (you can modify the stage, the units, and the leaf temperature adjustment) click here.


Why is VPD Important?


You probably already know that VPD is an important thing to keep track of in your grow’s environment, that’s why you’re looking it up. But why is VPD important? Getting your VPD right will give you the best results in your grow. VPD influences five key things, that are all somewhat related:

  1. Stomata Opening
    • As VPD increases, stomata get smaller. This is because the stomata are attempting to reduce water loss.
  2. CO2 uptake
    • As VPD increases and stomata get smaller, CO2 uptake gets reduced. Conversely, as VPD decreases and stomata open, CO2 uptake increases.
  3. Transpiration
    • As VPD increases, the plant transpires faster due to the larger difference in vapor pressures between the leaf and the air. Water tends to diffuse from areas of high concentration to areas of low concentration.
  4. Nutrient intake at the roots
    • As VPD increases, and transpiration increases, the roots pull in more nutrients. The plant is like one connected system of plumbing!
  5. Plant stress
    • As VPD increases, there are more forces acting on the plant – from the leaves to the roots – and the plant experiences more stress.

    As you can see there’s a complicated tradeoff between VPD and a variety of other factors. You can increase how much CO2 the plant absorbs by lowering VPD, but you’re also reducing the amount of nutrients the plant is pulling from the soil. You can increase the amount of nutrition, but you’re also stress the plant more and reducing CO2 intake. VPD is a very powerful tool in the grower’s toolbox. To get the best results you need to find the correct VPD sweet spot for the plant’s stage of growth.


    VPD and Indoor Growing


    Indoor growing comes with huge advantages. You have significantly more control over the environment that your plants grow in. Environment is one of those essential “knobs” you can twist when you’re growing indoors in order to get better results in your grow, and VPD is the key part of that formula.

    How you can influence and change VPD:

    1. Temperature
      1. Increase in temperature (run a heater or reduce AC): results in an increase of VPD because the SVP has increased
      2. Decrease in temperature (run AC): results in a decrease of VPD because the SVP has decreased
    2. Humidity
      1. Increase in humidity (run a humidifier): results in a decrease of VPD because the AVP has increased
      2. Decrease in humidity (run a dehumidifier): results in an increase of VPD because the AVP has decreased
    3. Light Intensity
      1. Increase in light intensity (move lights closer, add more lights): results in an of increase leaf temperatures, increasing VPD
      2. Decrease light intensity (move lights farther, remove lights): results in a decrease of leaf temps, decreasing VPD

    Ideal VPD for Different Stages of Growth

    So now you know what VPD is, how it impacts plants, and how you can change VPD. All that’s left is to figure out how to use this information in your own grow. The “Ideal VPD”, as a general rule for plant growth, is around 0.8 – 1.2 kPa (kilopascals). However, your plants have different needs during different stages of growth. You need to tailor your grow environment to the stage of growth that your plants are in. Below are some general recommendations, but keep in mind that these recommendations can vary from strain to strain, and setup to setup. As always, observe your plants and tweak things accordingly.

    Editor’s Note: Several of the growers we have interviewed HIGHLY recommend having a “test room” or “test tent” to experiment in before applying changes to your full-scale grow.

    1. Ideal VPD for Clones
      1. Clones are baby plants, they can’t handle a lot of stress because they are still just trying to form roots. Target a higher humidity and VPD closer to the lower end of the general range.
      2. The ideal VPD for clones is closer to 0.8 kPa.
    2. Ideal VPD for Vegetative Stage
      1. In veg (vegetative) stage, plants are bigger and more robust. You can reduce the humidity in your environment to increase VPD. This will increase water and nutrient uptake, but you don’t want to increase VPD too much. This will cause the stomata of the plants to close, causing them to absorb less CO2. CO2 is particularly important in the vegetative stage, because that’s one of the main ingredients for the sugars that make up the structural portions of plants.
      2. The ideal VPD for the vegetative stage is close to the middle of the general range, around 1.0 kPa.
    3. Ideal VPD for Flower Stage
      1. In flower stage, your plants are robust, but the flowers are sensitive to various issues. You need to avoid excess humidity, and increase VPD.
      2. The ideal VPD for the flower stage is closer to the top end of the range, 1.2kPa – 1.5kPa.

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    Feel free to post below!


    About the Author

    Hunter Wilson is a community builder with Growers Network. He graduated from the University of Arizona in 2011 with a Masters in Teaching and in 2007 with a Bachelors in Biology.


    A Review of Scientific Literature on the Relationship between Cannabis and Psychosis

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    Marco Troiani and Savino Sguera of Digamma Consulting look at the literature regarding Cannabis and psychosis. This is not “Reefer Madness,” this is real research.


    Editor’s Note: The following article is very dense in technical information. I have tried my best to simplify it for a layman’s understanding, but if you just want to read the conclusion, skip to the end.

    Americans are using Cannabis with increasing frequency to treat a wide variety of medical disorders. Despite the growth of medical Cannabis use in the United States, many still have concerns about certain issues of Cannabis safety. Cannabis has been scientifically shown to be less dangerous than alcohol and pharmaceutical drugs. This is largely due to the fact that Cannabis has significantly lower physical toxicity than other drugs, and does not promote harmful psychological effects such as destructive behavior and addictive tendencies that other common drugs might promote.

    However, there is one area of safety when it comes to Cannabis that scientific study has not revealed to be safer than traditional drugs: risk of psychosis. Although very rare, some people have experienced prolonged psychotic episodes after Cannabis use. In a majority of these cases, the patients affected are typically adolescents with a family history of schizophrenia. The evidence seems to suggest that the psychoactive component of Cannabis, THC, can trigger psychosis in certain individuals, but another component of Cannabis, CBD, can reverse psychosis.

    So, without further ado, here is our detailed and annotated examination of the evidence relevant to the relationship between Cannabis and psychosis:


    THC and Psychosis


    Large et al. 2011 Meta-Analysis

    Large et al. performed a meta-data analysis on many studies in 2011, and found an inverse correlation between adolescent use of Cannabis and the age at onset of psychotic disorders (mainly schizophrenia). In other words, in adolescents prone to psychosis, Cannabis seemed to accelerate the onset of said psychosis.

    The authors noted that much of the raw scientific data was derived from various studies that did not indicate whether Cannabis use predated the onset of psychosis, making the link correlational rather than causal. This means that the authors cannot be sure if the psychosis increases the likelihood of Cannabis use, or if the Cannabis increases the likelihood of psychosis, which is an important distinction.


      Large M, Sharma S, Compton MT, Slade T, Nielssen 0 (June 2011). "Cannabis use and earlier onset of psychosis: a systematic meta-analysis". Arch. Gen. Psychiatry 68 (6): 555-61. doi:10.1001/archgenpsychiatry2011.5. PMID 21300939

    Arseneault et al. 2004 Study

    According to Arseneault’s 2004 study, although Cannabis use is correlated with an earlier onset of psychosis in adolescents, they hypothesized that this phenomenon tends to occur in already at-risk groups, such as individuals with a family history of psychosis, or symptoms of psychosis predating Cannabis use.

    Unfortunately, our knowledge of how psychosis develops in the brain is limited. Additionally, our knowledge of how cannabinoid receptors develop and the role they play in psychosis is even more limited. This makes Arseneault’s hypothesis difficult to prove. Despite how difficult it is to prove this hypothesis, the literature indicates a pervasive acceptance of the idea that Cannabis use can exacerbate at-risk (of psychosis) youths.

    The authors’ language best describes the exact nature of the relationship: “Cannabis use appears to be neither a sufficient nor a necessary cause for psychosis. It is a component cause, part of a complex constellation of factors leading to psychosis.”


      Arseneault L, Cannon M, Witton J, Murray RM (2004). "Causal association between Cannabis and psychosis: examination of the evidence. The British Journal of Psychiatry 184(2): 110-117. doi:10.1192/bjp.184.2.110. PMID 14754822

    Caspi et al. 2005 Study

    Caspi et al’s 2005 study correlated the early onset of psychosis in Cannabis users with a specific polymorphism in the catecholamine o-methyltransferase gene, specifically the Valine-158 allele was the most likely to correlated with psychotic symptoms.

    Editor’s Note: For those not familiar with genetics lingo, a polymorphism is a change in a part of a gene that differs from the general population. Single nucleotide polymorphisms (abbreviated as SNPs) are changes in a single base-pair (A-T, or G-C), and are some of the most common examples of polymorphisms.

    This indicates that those who are at risk of psychosis may potentially learn about it through genetic testing. The paper even goes so far as to state that Cannabis users with a homozygous Methionine-158 genotype (in other words, a normal genotype) will have no adverse effects from Cannabis consumption.

    A later study conducted by Zammit et al in 2007 concluded that Cannabis use had no modulatory effects on psychotic symptoms nor did it interplay with either valine or methionine allele catecholamine o- methyltransferase, so the evidence is a little mixed on this one.


      Caspi A, Moffitt TE, Cannon M, McClayJ, Murray R, Harrington H, Taylor A, Arseneault L, Williams B, Braithwaite A, Poulton R, Craig IW (2005). "Moderation of the Effect of Adolescent-Onset Cannabis Use on Adult Psychosis by a Functional Polymorphism in the Catechol-O-Methyltransferase Gene: Longitudinal Evidence of a Gene X Environment Interaction". Biological Psychiatry 57 (10): 1117-27. doi:10.1016/j.biopsych.2005.01.026.PMID 15866551

    Henquet et al. 2005 Study

    The debate over whether Cannabis has a causal connection to schizophrenic onset in adolescents has been going on in the scientific community for some time, and has produced a wealth of literature. More importantly, the debate has resulted in empirical evidence on the subject. For example, Henquet’s 2005 study concludes that, “Cannabis use moderately increases the risk of psychotic symptoms in young people but has a much stronger effect in those with evidence of [a] predisposition for psychosis.”


      Henquet C, Krabbendam L, Spauwen J, Kaplan C, Lieb R, Wittchen HU, van OsJ (2005)."Prospective cohort study of Cannabis use, predisposition for psychosis, and psychotic symptoms in young people". BMJ 330 (7481): 11-0. doi:10.1136/ bmj.38267.664086.63.PMC 539839. PMID 15574485

    Moore et al. 2007 Study

    Conversely, Moore’s 2007 longitudinal study concluded with a very different tone: “The evidence is consistent with the view that Cannabis increases risk of psychotic outcomes independently of confounding and transient intoxication effects, although evidence for affective outcomes is less strong. The uncertainty about whether Cannabis causes psychosis is unlikely to be resolved by further longitudinal studies such as those reviewed here. However, we conclude that there is now sufficient evidence to warn young people that using Cannabis could increase their risk of developing psychotic illness later in life”


      Moore TH, Zammit S, Lingford-Hughes A, Barnes TR, Jones PB, Burke M, Lewis G (2007). "Cannabis use and risk of psychotic or affective mental health outcomes: a systematic review". The Lancet 370 (9584): 319-28. doi:10.1016lSOl40-6736 (07)61162-3. PMID 17662880


    CBD and Psychosis


    Zuardi et al. 2006 Study

    Zuardi et al’s 2006 study investigated CBD’s anti-psychotic nature, and found that its effects are broadly anxiolytic and antipsychotic. While it might seem that CBD serves only as an antagonist to THC’s psychosis-inducing effects, CBD is able to reverse anxiety in subjects who have not used cannabinoids before. This strongly suggests that CBD’s antipsychotic effects are independent of THC.

    In an experiment, mice were induced into psychosis by amphetamines and ketamines, which affect the dopaminergic neurons (D2) and glutaminergic neurons (NMDA), respectively. The psychoses triggered by both drugs were reversed by CBD administration. This indicates that CBD’s antipsychotic effects may have a broader pharmacological basis than just a few receptors. This is consistent with Campos et al’s 2012 theory that the TRVP1 receptor (of which CBD is an agonist) is responsible for contributing to CBD’s antipsychotic effects. Additionally, Zuardi’s team found that CBD was both a safe and efficient alternative treatment for schizophrenia.

    Editor’s Note: TRVP1 is colloquially referred to as the “capsaicin receptor” and is associated with the sensation of heat from spicy foods. Recently, I also learned that capsaicin can be used to reduce the effects cannabis hyperemesis syndrome, suggesting that this receptor can play multiple roles in regards to cannabis.


      Zuardi AW, Crippa JA, HallakJE, Moreira FA, Guimaraes FS (April 2006)."Cannabidiol, a Cannabis sativa constituent, as an antipsychotic drug". Braz. J. Med. Biol. Res. (Review) 39 (4): 421-9. doi:10.1590/SOl00-879X2006000400001.PMID 16612464

    Long et al. 2005 Study

    Long et al’s 2005 study investigated CBD’s ability to reverse Dizocilpine-induced psychotic symptoms in mice. Dizocilpine, also known as MK-801, is an NMDA agonist, and can be used in animals to experimentally induce the symptoms of schizophrenia.

    CBD did reverse the effects of Dizocilpine, but when it was co-administered with capsazepine, a TRVP1 antagonist, CBD’s effects disappeared. This evidence strongly suggests TRVP1’s role in CBD-treatable psychosis, and potentially its interrelation to several other neural systems.


      Long, L. E.; Malone, D. T.; Taylor, D. A. (2005). "Cannabidiol Reverses MK-801-lnduced Disruption of Prepulse Inhibition in Mice". Neuropsychopharmacology 31 (4): 795-803.doi:10.1038/sj.npp.1300838. PMID 16052245

    Leweke et al. 2012 Study

    Leweke et al’s 2012 study performed a clinical trial with schizophrenic patients comparing the efficacy of CBD against amisulpride. The study found that CBD was equally effective as amisulpride at treating psychotic symptoms of schizophrenia, but with a much reduced profile of side-effects. These findings indicate that proper use or drug-assisted optimization of the transmission of endocannabinoids can preclude harsher dopamine antagonist drug therapy.

    With THC’s rare but significant tendency to induce psychosis in adolescents, the question arises: Why does THC triggering the CB1 receptor cause psychosis, while anandamide triggering the same CBl receptor seem to reverse psychosis?

    One factor to consider is that the body’s natural endocannabinoid system. When THC is ingested and enters the brain, the CB1 receptors are triggered randomly and uniformly. This is not a normal, organized stimulus from the brain, and causes a degree of chaos and interference. CBD, on the other hand, inhibits the breakdown of endocannabinoids, which assists the body in transmitting normal signals. The natural feedback loop in the endocannabinoid system can prevent overstimulation of CB receptors, something that does not occur when ingesting THC. THC flows through the blood and cerebrospinal fluid, and will not target specific synapses, but rather target them all. These factors may reconcile the seemingly paradoxical relation between psychosis, CB1 receptors, and THC and CBD’s apparently opposite effects on the same receptor.

      Leweke, FM; Piomelli D, Pahlisch F, Muhl D, Gerth CW, Hoyer C, KlosterkotterJ, Hellmich M and Koethe D. (2012). "Cannabidiol enhances anandamide signaling and alleviates psychotic symptoms of schizophrenia". Translational Psychiatry 2 (3): e94-.doi:10.1038ltp.2012.15. PMC 3316151. PMID 22832859


    Summary


    Due to the complex relationship between Cannabis and psychosis, we have provided a brief summary of our research below:

      A summary of the findings relating THC and psychosis: Large’s study indicates a correlation between psychosis and adolescent Cannabis use. Arseneault’s study found a correlation as well, but described Cannabis use as neither necessary nor sufficient to cause psychosis, merely a component cause. Caspi’s study found a strong correlation between adolescents with Cannabis-induced psychosis and a specific genetic mutation, and postulates that genetic testing may indicate who is susceptible to Cannabis-induced psychosis in the general population. Henquet’s study found that most of the ability of Cannabis to induce psychosis was found in patients with a predisposition to psychosis. Moore performed longitudinal studies and found that adolescent Cannabis use correlated with higher probability of psychosis later in life.

      A summary of the findings relating CBD and psychosis: Zuardi’s study found that CBD was able to reverse psychosis caused by amphetamines and ketamines. Long’s study found that CBD reversed psychosis brought on by dissociative drug MK-801. Leweke’s study found found that CBD was as effective at treating schizophrenia as the FDA-approved drug amisulpride with a much reduced profile of side-effects.


    Editor's Note: Let us know your thoughts about this kind of article in the survey below.


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    Feel free to post below!


    About the Author

    Hunter Wilson is a community builder with Growers Network. He graduated from the University of Arizona in 2011 with a Masters in Teaching and in 2007 with a Bachelors in Biology.